This commit significantly refactors the alsa backend's `EventLoop::run`
implementation in order to allow for better error handling throughout
the loop. This removes many cases that would previously `panic!` in
favour of calling the user callback with the necessary error and
removing the corrupt stream. Seeing as the method cannot return, a
catch-all `panic!` still exists at the end of the method, however this
refactor should make it much easier to remove this restriction in the
future.
This adds the following types:
- `StreamEvent`
- `CloseStreamCause`
- `StreamError`
These allow for notifying the user of the following events:
- A stream has been played.
- A stream has been paused.
- A stream has been closed due to user destroying stream.
- A stream has been closed due to an error.
This allows for properly handling potential failure on macOS. We should
also consider propagating the mutex/channel poison errors through these
new types, especially considering the potential removal of the event
loop in favour of switching over to high-priority audio threads on
windows and linux.
The coreaudio and wasapi backends may both potentially fail to produce
the name associated with a device. This changes the API to allow for
returning the errors in these cases.
See the documentation for both new errors for details.
The new `DevicesError` has been added to allow for returning errors when
enumerating devices. This has allowed to remove multiple potential
`panic!`s in each of the alsa, coreaudio and wasapi backends.
Since #269 this `panic!` is certainly unnecessary as `InputBuffer` and
`OutputBuffer` are a thin wrapper around a slice. That said, I'm
struggling to understand exactly why this `panic!` was necessary in the
first place.
This closes#228.
- ALSA backend: reuse the buffers
- Make `InputBuffer` and `OutputBuffer` types just a wrapper of slice
* Buffer is now submitted at the end of callback
The internal alsa, null and emscripten Device implementations already
implemented Debug; but the coreaudio and wasapi ones, and therefore
also the wrapper, did not.
I decided to eschew the `Device(…)` wrapping in the outer layer
(hence a custom implementation rather than `#[derive(Debug)]`),
because `Device(Device)`, `Device(Device { … })` and so forth all
look better without the extra `Device(…)` wrapping.
On the wasapi and coreaudio implementations I put both the pointer and
name. Name because it’s useful, pointer because on Windows at least
I believe duplicated names are possible. (e.g. two monitors that include
monitors, of the same type; I haven’t strictly confirmed this, because I
killed those off harshly on my machine and don’t want to reinstate
them.)
I do not have access to a macOS device to confirm that the coreaudio
implementation is sane, but I think it is.
Instead of taking the easy way out and killing the whole program by panicking, device enumeration and stream creation will now report the error variant 'Unknown'
mitchmindtree
Mohanson
Tatsuyuki Ishi
Austin Johnson
Louis Pearson
Simon Repp
Chris Morgan
Florian Vick
azyobuzin
Ben Boeckel
Andre-Philippe Paquet